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        "%matplotlib inline"
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        "\n# SVM Margins Example\n\nThe plots below illustrate the effect the parameter `C` has\non the separation line. A large value of `C` basically tells\nour model that we do not have that much faith in our data's\ndistribution, and will only consider points close to line\nof separation.\n\nA small value of `C` includes more/all the observations, allowing\nthe margins to be calculated using all the data in the area.\n\n\n"
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      "source": [
        "print(__doc__)\n\n\n# Code source: Ga\u00ebl Varoquaux\n# Modified for documentation by Jaques Grobler\n# License: BSD 3 clause\n\nimport numpy as np\nimport matplotlib.pyplot as plt\nfrom sklearn import svm\n\n# we create 40 separable points\nnp.random.seed(0)\nX = np.r_[np.random.randn(20, 2) - [2, 2], np.random.randn(20, 2) + [2, 2]]\nY = [0] * 20 + [1] * 20\n\n# figure number\nfignum = 1\n\n# fit the model\nfor name, penalty in (('unreg', 1), ('reg', 0.05)):\n\n    clf = svm.SVC(kernel='linear', C=penalty)\n    clf.fit(X, Y)\n\n    # get the separating hyperplane\n    w = clf.coef_[0]\n    a = -w[0] / w[1]\n    xx = np.linspace(-5, 5)\n    yy = a * xx - (clf.intercept_[0]) / w[1]\n\n    # plot the parallels to the separating hyperplane that pass through the\n    # support vectors (margin away from hyperplane in direction\n    # perpendicular to hyperplane). This is sqrt(1+a^2) away vertically in\n    # 2-d.\n    margin = 1 / np.sqrt(np.sum(clf.coef_ ** 2))\n    yy_down = yy - np.sqrt(1 + a ** 2) * margin\n    yy_up = yy + np.sqrt(1 + a ** 2) * margin\n\n    # plot the line, the points, and the nearest vectors to the plane\n    plt.figure(fignum, figsize=(4, 3))\n    plt.clf()\n    plt.plot(xx, yy, 'k-')\n    plt.plot(xx, yy_down, 'k--')\n    plt.plot(xx, yy_up, 'k--')\n\n    plt.scatter(clf.support_vectors_[:, 0], clf.support_vectors_[:, 1], s=80,\n                facecolors='none', zorder=10, edgecolors='k')\n    plt.scatter(X[:, 0], X[:, 1], c=Y, zorder=10, cmap=plt.cm.Paired,\n                edgecolors='k')\n\n    plt.axis('tight')\n    x_min = -4.8\n    x_max = 4.2\n    y_min = -6\n    y_max = 6\n\n    XX, YY = np.mgrid[x_min:x_max:200j, y_min:y_max:200j]\n    Z = clf.predict(np.c_[XX.ravel(), YY.ravel()])\n\n    # Put the result into a color plot\n    Z = Z.reshape(XX.shape)\n    plt.figure(fignum, figsize=(4, 3))\n    plt.pcolormesh(XX, YY, Z, cmap=plt.cm.Paired)\n\n    plt.xlim(x_min, x_max)\n    plt.ylim(y_min, y_max)\n\n    plt.xticks(())\n    plt.yticks(())\n    fignum = fignum + 1\n\nplt.show()"
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